The store said on Monday there had been no rats caught at the premises in more than a week.
This afternoon, Woolworths New Zealand director of stores Jason Stockill said the store would close at 10pm tonight for at least 48 hours so pest control efforts can be stepped up in light of the new captures.
"Our local community will be aware that we’ve been working to address a rodent issue at Countdown Dunedin South for the last couple of months, Mr Stockill said.
"Food safety is our absolute priority and we have been working closely with the Ministry for Primary Industries’ (MPI) NZ Food Safety division and our pest control contractor Rentokil.
"We believed we had addressed the issue, as there had been no evidence of rodent activity since January 28.
"Unfortunately, we have caught four rodents over the last few days so it is clear we have more work to do.
Countdown Dunedin South would close for the next 48 hours after it became clear the pest management plan in place was " not working as effectively as anticipated".
The store would close in order for additional pest control efforts to have complete access to the whole store.
NZ Food Safety was also working with the Dunedin City Council surveying neighbouring areas as part of a co-ordinated response.
"Having a safe and hygienic store is incredibly important to us and we would like to apologise to our customers for any distress and inconvenience this update causes.
"We will reopen when we are confident these additional measures have been implemented. We anticipate this will be on Monday morning," he said.
The issue first came to light after staff members last month told the Otago Daily Times rats were running rampant in the store and they feared the public could have been sold contaminated food.
A photo, taken in November last year, was then supplied to the ODT showing a rat in the deli section.
A store employee, who spoke on the condition of anonymity, said "one or two" rats were first detected inside the store in October.
Since then, they had multiplied leading to the store becoming "infested".
They believed store management had not done enough to address the issue, but a Woolworths New Zealand spokesman said the company’s pest control programme had significantly reduced the problem since the November photo was taken.
This week a staff member said there was still evidence of rat activity in the store but it appeared there were less rats at the store than previously.
In response a Woolworths New Zealand spokesman said there had been no new captures in more than a week and the situation was being addressed appropriately with a comprehensive pest management plan.
